1. Field of the Invention
The present invention relates to a fiber laser apparatus comprising an amplifying optical fiber and to a laser processing method using the fiber laser apparatus.
2. Related Background Art
A fiber laser apparatus comprises an amplifying optical fiber, and by supplying pumping light together with seed light, the seed light is amplified as a processing laser beam. Since such a fiber laser apparatus can output a high-quality and high-power laser beam, it can be advantageously used in the field for laser processing. An apparatus disclosed in “Processing Technology Using High-output Laser, In-process Monitoring and Evaluation of Processing State”, published on May 9, 2005, by Gijutsu Joho Kyokai, is known as a conventional fiber laser apparatus.